Door check



Jan. 7, 1941. w. H. LINDSAY DOOR CHECK Filed Aug. 7, 1959 1 mTIIIIIIIIIIIIIIIIIIIII)AMI nvz/s/v 727 W\LLIAM H. LINDSAY Patented Jan.7, 1941 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates generally to devices for controlling themovements of the door and particularly to a hydraulic means for checkingthe closing operation of a door.

The main object of this invention is to construct a door check whichwill operate satisfactorily over a long period of time without attentionor adjustment regardless of atmospheric conditions.

The second object is the construction of a door check which will beinexpensive to manufacture and adjust for a given condition and easilyinstalled under limited space conditions.

The third object is toconstruct a door check which will be extremelyrigid at its position of fastening to the door frame and at the sametime be easily interchangeable from a check for the door itself to thescreen door thereof.

The fourth object is to construct a hydraulic door check from which itwill be impossible for the fluid to leak out at any time.

The fifth object is to construct a special form of valve mechanism for ahydraulic door check in which the resistance can be entirely removed 25or selectively applied to the operating mechanism thereof.

These and other objects are accomplished in the manner set forth in thefollowing specification as illustrated in the accompanying drawing, inwhich:

Fig. 1 is a fragmentary elevation of the corner of the door and doorframe showing the door check broken away in vertical sections, andshowing the door in a closed position.

Fig. 2 is a horizontal section taken along line 2-2 in Fig. 1.

Fig. 3 is an enlarged longitudinal section of the operating cylinder,showing the valve in an open position.

Fig. 4 is a section taken along the line 4--4 in Fig. 3.

Fig. 5 is a transverse section taken along the line 5-5 in Fig. 3showing the position of the Valve.

Similar numerals refer to similar parts throughout the several views.

Before entering into the description of this invention, it is understoodthat numerous forms of door checks of this general type have beenconstructed in the past, most of which employ air as the operatingfluid. Such devices are not only diificult to adjust for a givencondition but are also seemingly difiicult to maintain in adjustmentowing to the variable conditions under which the devices operate. Thepurpose of using a hydraulically operated check is to facilitate theoperation thereof and insure a continued uniform operation which isunaffected by changes in temperature, or moisture, or the dust ladencontent of the surrounding air. 5 Referring in detail to the drawing,there is shown a door I!) which is mounted within the frame I I by meansof a hinge not shown. The

position of the frame head I2 is also indicated referring in particularto the invention the same 10 will be seen to consist of a hydrauliccylinder l3 whose lower end I4 is threaded and closed by means of a cap[5, the union being sealed by the gasket I6. The cap l5 has attachedthereto a hinge I! which is fastened to the door 10 by 1 means of thescrew l8.

Within the cylinder I3 is mounted a tubular piston Hi, to one end ofwhich is hinged the circular valve 20 by the pin 2|. Within the memberI9 is formed the lug 22 through which is threaded 20 the adjustmentscrew 23 which limits the movements of the valve 20 in the closingdirection. The cylinder [3 has threaded on its upper end a cap 24 whichpreferably contains a gasket 25. Extending axially through the cylinder[3 is a. 25 piston rod 26. Through the lowermost end 21 extends thepiston pin 28 which also extends through the piston IS.

The U shaped'bracket is secured to the door frame par-ts H and I2 bymeans of the screws 30 30 and 3!. Mounted on the bracket 29 is avertical pin 32 on whose upper end is secured an arm 33 to which ishingedly connected the upper end 34 of piston rod 26 by means of therivet 35. Between the arm 33 and the opposite end .36 of 35 the bracket29 are placed the collars 31 and 38 between which is disposed thetorsion spring 39 whose end 40 bears against the bracket portion 36,also end 4| bears against the piston rod 26.

The operation of the device is as follows:

With the parts in the position shown in Fig. 1 and a quantity of liquidplaced within the cylinder l3 and the door It in a closed position itwill be seen that when the door It is opened the piston ill will bedrawn away from the lower end of the cylinder I3 without any resistancebeing offered to such movements due to the fact that the valve 20 opensfreely in that direction but when an attempt is made to close the dooror it 50 is closed under the action of the spring 39, there is amovement in the opposite direction the first portion of which causes thevalve 20 to close as tightly as permitted by the screw 23 to provide thedesired resistance to the closing action of 5 the door. This can beincreased and decreased by varyingthe setting of the screw 23.

If the check is to be used on a screen door for a portion of the time itis only necessary to remove the screw l8 and turn the cylinder I3 180degrees and insert the screw I8 into the opposite door where it willfunction as before.

It will be observed that by placing the screw 3| on the end of thebracket 29 and the screw 30 on the base thereof that the utmost rigidityis provided for the bracket. The outstanding advantage of this deviceresides in its continued uniformity of operation, and once adjusted, itsaction remains the same under all conditions until that adjustment ischanged. It will also be observed that due to the angle of inclinationit is not possible for any of the liquid 42 to leak out or escape fromthe cylinder even though the cylinder be maintained in an almostcompletely filled condition.

I claim:

1. A door check having in combination an inclined hydraulic cylinder, acap on the lower end of said cylinder hingeable to a door, a tubularpiston within said cylinder having a valve across its lower end adaptedto close upon a downward movement of said piston, means for limiting thedegree of closing, a piston rod having its lower end connected to saidpiston and having its upper end projecting from said cylinder, and aspring urged arm hingedly attachable to a door frame having its swingingend hinged to the upper end of the piston rod.

2. A door check consisting of an inclined hydraulic cylinder closed atits lower end and having a piston rod therein projecting from its upperend, a tubular piston within said cylinder connected to the lower end ofsaid piston rod, a circular gate hinged to one end of said tubularpiston having means for limiting the closing action thereof, a bracketattachable to a door frame and having an arm pivotally mounted thereon,said arm being hinged to the uppermost end of said piston rod and atorsion spring on said bracket adapted to urge said rod in a doorclosing direction.

WILLIAM H. LINDSAY.

